GB1180743A - Novel Flourinated Heterocyclic Compounds - Google Patents

Abstract

1,180,743. Perfluorinated heterocyclic compounds; diphenyl and diphenyl sulphide derivatives. NATIONAL RESEARCH DEVELOPMENT CORP. 29 June, 1967 [29 June. 1966], No. 29271/66. Heading C2C. Novel tricyclic compounds of the Formula (I) wherein R and R<SP>1</SP> each represents an oxygen or sulphur atom or an -SO 2 - radical or R represents a direct bond between the benzene nuclei and R<SP>11</SP> is a fluorine atom or an amino, alkoxy or hydroxy group are prepared (1) by cyclizing compounds of the formula (II), wherein each X is a fluorine atom or a bromine atom ortho to the thioether bond, (e.g. when X is a bromine atom, by reaction with copper to give compounds in which R is a direct bond, or when X is a fluorine or bromine atom, by reaction with n-butyl lithium, followed by reaction with sulphur dichloride to give compounds in which R is a sulphur atom), or (2) by interconversion from other compounds of Formula (I), e.g. by reacting compounds in which R<SP>11</SP> is a fluorine atom with ammonia or an aikoxide to give the corresponding compounds in which R<SP>11</SP> is an amino or alkoxy group or by reacting compounds in which R or R<SP>1</SP> is a sulphur atom with trifluoroacetic anhydride and hydrogen peroxide to obtain the corresponding S-dioxides and, if desired, subliming those at low pressure to obtain the corresponding compounds in which R or R<SP>1</SP> is an oxygen atom. The fluorinated diphenyl derivatives 2,2<SP>1</SP>- dihydro - octafluorodiphenyl and 2,2<SP>1</SP>- dihydro- 5-methoxy-heptafluorodiphenyl are obtained by hydrogenating octafluorodibenzothiophene and 2-methoxyheptafluorodibenzothiophene respectively. Thioethers of the Formula (II) are obtained by reacting bromopentafluorobenzene or 1,2- dibromotetrafluorobenzene with n-butyl lithium and treating the product with sulphur dichloride.